For a direct injection type of an internal combustion engine of an automobile or the like where a fuel is directly injected to the inside of a combustion chamber, a high pressure fuel supply pump including an electromagnetic suction valve for highly pressurizing a fuel and discharging a desired fuel flow rate is widely used.
PTL 1 discloses a damper as a pressure pulsation reduction mechanism for reducing a low pressure pressure pulsation of a high pressure fuel supply pump, and a method of fixing the same. Pressure pulsation on a low pressure side occurs as a pressurizing member (plunger) is repeatedly reciprocatingly moved in a sliding manner in a cylinder.